As is well known and understood, in retinal eye repair surgery, it is very highly desirable for the surgeon to view as much of the retina as possible. Wide-angle viewing objective lenses have been developed by microscope manufacturers to aid in this. However, and because of back-reflected light, the illumination of the retina cannot generally be had through the same microscope lens. As a result--and as is also understood--, an opening is thus made in the eye, where a fiber optic cable is then inserted that provides a beam of light to illuminate the retinal area.
A significant problem with such an arrangement was recognized when it was realized that the largest fiber optic beam that could be obtained was only of the order of 0.25 inches in diameter; thus, attempts at increased beam-spreading the relatively coherent light were tried. Such attempts proved highly unsuccessful in practice, though, especially when placing a lens on the end of the fiber optic cable--as analysis showed that providing any type of light refracting lens on the surface of the fiber optic cable was for the most part cancelled out, and due to the light refracting index matching of the vitreous eye fluid to that of the light refracting lens material which came in contact with such fluid. It was also found that making and aligning very small lenses was very difficult. Additional approaches to overcome this problem also prove of limited usefulness in that the light spreading that is achieved is essentially omnidirectional--i.e. spread 360.degree.--, instead of being focused in the retinal area of concern. Additionally, and because such approaches provide a near 360.degree. omni-directional angle of dispersion, it was determined that a significant portion of the light being spread also is directed back through the eye lens and microscope lens through which the surgeon viewed the retina, thus producing a glare. Also, valuable light is dispersed onto areas where no viewing can be achieved.